<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <style>
        button{
            height: 16px;
            width: 16px;
            border-style: none;
            border-radius: 8px;
            text-align: center;
            line-height: 16px;
            padding-top: 0px;
            padding-left: 4px;
        }
        .zheng{
            background-color: lightskyblue;
            color: white;
        }
        .fu{
            color: lightskyblue;
            background-color: white;
            border: solid lightblue;
        }
    </style>
</head>
<body>
    <div id="app">
        <button class="fu" @click="count--" v-show="count > 0">-</button><span>{{count}}</span><button class="zheng" @click="count++">+</button>
    </div>
    <script>
        const {createApp} = Vue
        createApp(
            {
                data(){
                    return {
                        count:0
                    }
                },
                methods: {
                    
                },
            }
        ).mount("#app");
    </script>
</body>
</html>